Concrete formwork brace and method of bracing concrete formwork

ABSTRACT

A concrete formwork brace having a base, a bracket configured to support a concrete formwork and a pair of adjustable arms. A first length adjustable arm is connected to the base and the bracket and a second arm is connected to the base and the bracket. The connection between the first arm and the base is vertically offset from the connection between the second arm and the base and the connection between the first arm and the bracket is vertically offset from the connection between the second arm and the bracket. The first arm is length adjustable such as to adjust the orientation of the bracket.

FIELD OF THE INVENTION

The invention relates to concrete formwork braces and methods of bracingconcrete formwork.

BACKGROUND TO THE INVENTION

In the construction industry concrete forms, or formwork includebarriers and moulds that hold concrete or other cementitious materialwhile it hardens to assume a desired shape. Braces have been suggestedto hold the formwork in the required position, resisting the strongforces which wet concrete exerts against formwork. For example, woodprops may be anchored to the ground with pegs and secured to formwork.This often results in damage to the formwork and wooden props as screwsor other fasteners create holes in the wood. Such systems of woodenbracing can be wasteful and costly.

Removing bracing from the formwork is often invasive as fasteners arepried out. Concrete that has not sufficiently hardened will be damagedby early removal of bracing or formwork. Generally, current types ofbracing must stay in place at least overnight.

Although prior braces can be fastened in different positions to providesome variation in position, once the braces are fastened to the formworkthey are generally set in place and they cannot be re-adjusted withoutun-fastening and refastening.

To provide some adjustment, bracing has been provided with an extendablestrut or arm. Other known braces have employed “pivot points” forangular adjustment of a diagonal strut included in the brace. Howeverthe ability to readily adjust the brace can sometimes compromise therigidity of the brace and its ability to keep the formwork in place.Furthermore, improvements can be made to the precision and ease of braceadjustments.

Prior braces have failed to rest properly on uneven or sloping surfaceswithout compromising the functioning of the brace.

Prior braces are often difficult and cumbersome to assemble, andtherefore time-consuming to install.

Reference to any prior art in this specification does not constitute anadmission that such prior art forms part of the common generalknowledge.

It is an object of the invention to provide an improved concreteformwork brace and/or method of bracing which overcomes or at leastameliorates some or all of the above shortcomings, or to at leastprovide the public with a useful choice.

SUMMARY OF THE INVENTION

According to one aspect the invention provides a concrete formwork braceincluding: a base, a bracket configured to support a concrete formwork,a first length adjustable arm, connected to the base and the bracket,and a second arm connected to the base and the bracket; wherein theconnection between the first arm and the base is vertically offset fromthe connection between the second arm and the base, wherein theconnection between the first arm and the bracket is vertically offsetfrom the connection between the second arm and the bracket; and whereinthe first arm is length adjustable such as to adjust the orientation ofthe bracket.

Preferably the second arm is length adjustable.

Preferably the connection between the first arm and the base ishorizontally offset from the connection between the second arm and thebase.

Preferably the connection between the first arm and the base is at afirst end of the base and the connection between the second arm and thebase is at an intermediate position between the first end of the baseand a second end of the base.

Preferably the connection between the second arm and the base iscentrally located on the base.

Preferably the connection between the second arm and the base isvertically elevated relative to the connection between the first arm andthe base.

Preferably the base has mounting features for securing the base to aground surface.

Preferably the mounting features are apertures configured to receivefasteners for securing the base to a ground surface.

Preferably the bracket has mounting features for securing the bracket toformwork.

Preferably the bracket has apertures configured to receive fastenerssecuring the bracket to formwork

Preferably the bracket is configured to rest, in use, on a groundsurface.

Preferably the bracket is height-adjustable.

Preferably the brace includes a level indicator.

Preferably the first length adjustable arm is length-adjustable byrotation of a threaded element.

Preferably the second arm is length-adjustable by rotation of a threadedelement.

Preferably the connection between the first arm and the bracket is apivotal connection and the connection between the second arm and thebracket is a pivotal connection.

Preferably the connection between the first arm and the base is apivotal connection and the connection between the second arm and thebase is a pivotal connection.

This aspect also extends to a method of bracing a concrete formwork, themethod including the steps of: arranging the concrete formwork braceadjacent the concrete formwork, with the bracket facing the concreteformwork, securing the base to the ground or other underlying support;adjusting one or more of the first and second arms relative to the baseand the bracket, to adjust the orientation and/or position of thebracket.

According to a second aspect the invention provides a concrete formworkbrace including: a base; and a bracket supported by the base, thebracket including: a first engagement element configured to engage witha cooperating second engagement element on a concrete formwork to definea releasable connection between the bracket and the formwork.

Preferably the releasable connection is a clamp connection.

Alternatively the releasable connection is a hook connection.

Preferably, in use, in an engaged state the bracket is flush against theformwork.

Preferably the second engagement element includes a protrusion.

Preferably the protrusion is located in a recess of the bracket when thebracket and the formwork are connected.

Preferably the actuator is a lever.

Alternatively the actuator is a latch.

Alternatively the actuator is a twist lock actuator.

Preferably the actuator is removable from the bracket.

Preferably the formwork is wooden.

Alternatively the formwork is metal.

Optionally the second engagement element is inserted into a channel inthe formwork.

Preferably the second engagement element acts as a spacer when formworkis arranged in stacks.

This aspect also extends to a method of releasably engaging formwork toa concrete formwork brace, the method including the steps of: creatingor securing a second engagement element on the formwork, arranging theconcrete formwork brace adjacent the formwork, with the bracket facingthe concrete formwork, and; engaging the first engagement element withthe second engagement element.

This aspect also extends to a concrete formwork system including: one ormore concrete formwork braces; and concrete formwork including one ormore second engagement elements configured to cooperate with one of thefirst engagement elements.

This invention also extends to concrete formed by the method of thefirst aspect and/or the method of the second aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described by way of example only, withreference to the accompanying drawings, in which:

FIG. 1 shows a perspective view of a concrete formwork brace accordingto an embodiment of the present invention;

FIG. 2 shows a right side view of the concrete formwork brace of FIG. 1;

FIG. 3 shows a back view of the concrete formwork brace of FIG. 1;

FIG. 4 shows a front view of the concrete formwork brace of FIG. 1;

FIG. 5 shows a top view of the concrete formwork brace of FIG. 1;

FIG. 6 shows a left side view of the concrete formwork brace of FIG. 1;

FIG. 7 shows a bottom view of the concrete formwork brace of FIG. 1;

FIG. 8 shows a front view of a concrete formwork brace with the bracketarranged in a first exemplary inclination;

FIG. 9 shows a front view of a concrete formwork brace with the bracketarranged in a second exemplary inclination;

FIG. 10 shows a set of concrete formwork braces according to anembodiment of the present invention supporting formwork;

FIG. 11 a shows an embodiment of a second engagement element accordingto an embodiment of the present invention;

FIG. 11 b shows a cross section of the second engagement element of FIG.11 a;

FIG. 12 shows another embodiment of a second engagement elementaccording to an embodiment of the present invention;

FIG. 12 a shows an end view of the second engagement element shown inFIG. 12;

FIG. 13 a shows another embodiment of a second engagement elementaccording to an embodiment of the present invention;

FIG. 13 b shows a cross section of the second engagement element of FIG.13 a;

FIG. 14 shows another embodiment of a second engagement elementaccording to an embodiment of the present invention;

FIG. 15 shows another embodiment of a second engagement elementaccording to an embodiment of the present invention;

FIG. 16 shows another embodiment of a second engagement elementaccording to an embodiment of the present invention;

FIG. 17 shows another embodiment of a second engagement elementaccording to an embodiment of the present invention;

FIG. 18 shows a bracket releasably secured to formwork according to anembodiment of the present invention; and

FIG. 19 shows a pile of stacked formwork according to an embodiment ofthe present invention.

DETAILED DESCRIPTION

The invention relates to concrete formwork braces and methods of bracingconcrete formwork. “Concrete” in this context may relate to anycementitious material used in construction which hardens to assume adesired shape or configuration including but not limited to materialsincluding concrete, cements and limes. “Formwork” includes any suitablebarriers or moulds for supporting concrete in a desired shape orconfiguration while it hardens. This may include wooden, metal orplastic formwork, but the invention is not limited in this respect.Formwork may be used in formation of concrete slabs, foundations,panels, monolithic structures or any other suitable cementitiousstructure.

FIGS. 1-7 show a concrete formwork brace 1 according to an embodiment ofthe present invention. The brace 1 includes a base 2 and a bracket 3configured to support a concrete formwork (not shown). The brace 1includes a first length adjustable arm 4 and a second arm 5. The firstarm 4 is length adjustable such as to adjust the orientation of thebracket 3 relative to the base 2. Preferably, the second arm 5 is alsolength adjustable, however in some embodiments this is not a necessity.In other embodiments the second arm may be length adjustable while thefirst arm is fixed in length.

Both the first arm 4 and the second arm 5 are pivotally connected to thebracket 3. In some embodiments the first arm 4 and the second arm 5 mayalso be pivotally connected to the base 2. As shown in FIG. 2, theconnection 6 between the first arm 4 and the base 2 is vertically offsetfrom the connection 7 between the second arm 5 and the base 2. Thevertical offset is shown by arrow A of FIG. 2. In the embodiment shownthe connection 7 between the second arm 5 and the base 2 is verticallyelevated relative to the connection between the first arm 4 and thebase. The vertical offset provides improved adjustability of thebracket, and also allows room to insert a power tool to adjust thelength of the first arm 4 or the second arm 5, as discussed below.

Further, the pivotal connection 8 between the first arm 4 and thebracket 3 is vertically offset from the pivotal connection 9 between thesecond arm 5 and the bracket 3. This vertical offset is shown by arrow Bin FIG. 2. Thus the four pivotal connections 6, 7, 8 and 9 are arrangedin a quadrilateral shape. This provides a highly stable and adjustablestructure.

Preferably, the connection 6 between the first arm 4 and the base 2 isalso horizontally offset from the connection 7 between the second arm 5and the base 2. This horizontal offset is shown by arrow C in FIG. 2.The pivotal connection 6 between the first arm 4 and the base 2 ispreferably at a first end 10 of the base 2 and the pivotal connection 7between the second arm 5 and the base 2 is at an intermediate pointbetween the first end 10 of the base 2 and a second end 11 of the base.The pivotal connection 7 between the second arm 5 and the base 2 may begenerally centrally located on the base 2.

Referring now to the top view of FIG. 5, the base 2 will preferably havemounting features 12 for securing the base 2 to a ground surface. Inthis embodiment, the mounting features are apertures 12 through whichstakes (not shown) can be inserted to secure the base 2 to the ground. Aperson skilled in the art can readily envisage other ways in which tosecure the base to the ground, and the invention is not limited in thisrespect.

Preferably, the bracket 3 also includes mounting features for securingthe bracket 3 to concrete formwork. In the shown embodiment, these areapertures for receiving fasteners (screws, nails etc), however they maybe any other suitable mounting features. As will be discussed later inthe specification, in an alternative embodiment these mounting featuresmay be part of a quick release mechanism for attachment/release of thebracket to/from the formwork.

In use the bracket 3 may rest on a ground surface. This is accomplishedby way of a foot 14 (FIG. 1).

The concrete formwork brace 1 may also include a level indicator (notshown), for assisting a user to arrange the geometry of the brace in adesired orientation.

The length-adjustment of the arms may be effected through any suitablemechanism. In the shown embodiment, arm length is adjusted by rotationof a threaded element. This may be adjusted manually or using a powertool. A first portion 5 a of each arm includes a threaded section (notvisible in FIG. 2). A handle portion 5 b has internal threadingcomplimentary to that of threaded section of the first portion 5 a. Asthe handle portion 5 b is rotated, it drives the first portion 5 a toextend or retract the first portion relative to the handle 5 b. Thislengthens or shortens the overall length of the arm 5. The arm 4 may besimilarly constructed.

In order to adjust the length of the first or second arm 4, 5, a usermay manually twist the handle portion 5 b. Alternatively, theApplicant's brace allows powered adjustment of arm length. Each armincludes a drive head 4 c, 5 c, with a suitable shape for receiving adrive bit from a power tool such as a handheld power drill. Each drivehead 4 c, 5 c is linked to the threaded drive mechanism described above.Rotation of the drive head 4 c, 5 c will cause rotation of the handleportion 4 b, 5 b relative to threaded section of each first portion 4 a,5 a of the arms 4, 5.

FIGS. 8 and 9 show the bracket 3 in two different positions relative tothe base, in order to illustrate the adjustability of the bracket'sposition and orientation.

FIG. 8 shows a front view of a concrete formwork brace with the bracketarranged in a first exemplary inclination. In this embodiment the secondarm 5 has been extended relative to the first arm 4 to push the upperpart of the bracket 3 outwards, thus creating an inclined orientation ofthe bracket.

FIG. 9 shows a front view of a concrete formwork brace with the bracketarranged in a second exemplary inclination. In this embodiment the firstarm 4 has been extended relative to the second arm 5 to push the lowerpart of the bracket 4 outwards, thus creating an orientation of thebracket with the opposite inclination to that shown in FIG. 8.

Further, the bracket 3 may include a first portion 3 a mounted to thefirst and second arms and a second portion 3 b mounted to the firstportion 3 a. The second portion 3 b may be adjustable relative to thefirst portion by rotation of a drive screw with a head 3 c. The drivescrew may be adjusted manually or using a power tool such as a handheldpower drill. In FIG. 9 the second portion 3 b is relatively extendedcompared to the position shown in FIG. 8.

To brace concrete formwork using the brace 1, a user may arrange thebrace 1 adjacent the concrete formwork, with the bracket 3 facing theconcrete formwork. Then the user may secure the base 2 to the ground orother underlying support (for example, using the mounting features 12).Then the user may adjust one, or both of the first and second armsrelative to the base 2 and the bracket 3, to adjust the orientationand/or position of the bracket relative to the base. The user may alsoadjust the height of the brace 3. The user may attach the bracket toformwork using screws or other fasteners, or using a quick releasemechanism such as described below. In practice a plurality of braceswill generally be arranged to support a formwork. The user may fine tunethe brace adjustments once two or more, or all, of the braces are inposition.

FIG. 10 shows a set of concrete formwork braces according to anembodiment of the present invention supporting formwork 15. Any numberof braces 1 may be arranged in any suitable arrangement to support theconcrete formwork.

Another aspect of the invention relates to a quick-release mechanism forreadily attaching and detaching concrete formwork braces to formwork.

FIGS. 11-20 show various releasable connection arrangements forconnecting a concrete formwork brace to concrete formwork. In each casethe releasable connection arrangement includes a first engagementelement 16 on the bracket 3, configured to engage with a cooperatingsecond engagement element 17 on a concrete formwork 15 to define areleasable connection between the bracket 3 and the formwork 15.

FIGS. 11-18 shows different embodiments of the second engagement element17 on concrete formwork 15. The releasable connection between thebracket 3 and the formwork 15 may be any suitable releasable connection,for example a releasable clamp connection or a releasable hookconnection. A releasable connection is one where the bracket and theformwork can be readily engaged and disengaged from each other withoutdamage to formwork.

FIG. 11 a shows an embodiment wherein the second engagement element 17is a protrusion having a T-shaped profile. FIG. 11 b shows a crosssection of the second engagement element 17. The second engagementelement 17 includes a narrow neck 19 and a wider head portion 20. Thefirst engagement element 16 is a clamp element which in an engaged stateis clamped around head portion 20 of second engagement element 17. Anactuator 18 (in the shown embodiment, a lever), is toggled to clamp andunclamp the second engagement element 17. A base portion 21 of thesecond engagement element 17 holding the neck 19 and the head 20 ispermanently attached to the formwork 15.

FIG. 12 shows an embodiment wherein the second engagement element 17 isattached to the formwork 15 by cutting a hole in the formwork (forexample wooden formwork), and inserting the second engagement element17. The second engagement element 17 is in this case a cylindricalbracket mount which protrudes from the formwork. A suitable firstengagement element (not shown) may be provided to engage with the secondengagement element 17. FIG. 12 a is a side view showing the installedsecond engagement element 17 protruding from the surface of the formwork15.

FIGS. 13 a and 13 b show an embodiment wherein the second engagementelement 17 is mounted to the formwork 15 by insertion through a channel.For example, this may be custom metal extruded formwork 15 with achannel for sliding bracket mounts. The embodiment of FIG. 13 a may besuited to a second engagement element 17 having a cross section similarto that of FIG. 11 b. FIG. 13 b shows a side view of the formwork 15 ofFIG. 13 a with the second engagement element positioned within thechannel. The formwork 15 includes an opening 22. This opening is wideenough to admit the neck 19 of the second engagement element 17, howeverit is narrow than the base 21 of the second engagement element 17, suchthat the second engagement element 17 cannot escape through the opening22. A channel is formed by lips 23 is provided inside the formwork 15 ofdimensions slightly greater than that of the base 21. Thus the base canslide within the channel.

FIG. 14 shows an embodiment wherein the second engagement element 17 isfixed directly to a formwork surface with screws or other suitablefasteners. The second engagement element 17 may have a T-shaped profilesimilar to that of FIG. 11 b, or it may have any other suitable shapethat cooperates with a corresponding first engagement element 16.

FIGS. 15-18 show further examples of second engagement elements 17cooperating with first engagement elements 16 to form a releasableconnection.

FIG. 15 shows an embodiment in which the first engagement element 16 isa cylindrical disk and the second engagement element 17 is a channelconfigured to receive the first engagement element 16. Unlike theembodiment of FIG. 13, in which the channel was part of the formworkitself, in this embodiment the channel is fastened to the formwork (notshown) and protrudes from it. The cylindrical disk or flange 16 may beslid into the channel from the top.

FIG. 16 shows an embodiment wherein the first engagement element 17includes rectangular apertures 24, and the second engagement element 16includes hooks 25 that hook into the apertures 24. The actuator 18 inthis embodiment is a lever, which can be rotated to move the hooks 16 upor down, into or out of the apertures 24.

FIG. 17 shows an embodiment wherein the first engagement element 16 hasa complimentary shape to the second engagement element 17. Thisembodiment may provide a twist lock mechanism. The second engagementelement 17 fits around the first engagement element 16 like a lock andkey. The actuator can be twisted to lock the first engagement element 16around the second engagement element 17.

Preferably, in an engaged state the bracket 3 is flush against theformwork. FIG. 18 shows an embodiment where this is the case. The secondengagement element 17 includes a protrusion (T-shaped protrusion). Thebracket 3 includes a recess which contains first engagement element 16.In an engaged state, the second engagement element 17 locates itselfwithin the recess of the bracket 3. The bracket 3 is pulled towardsformwork 15 in this configuration, such that it is flush against theformwork.

The concrete formwork brace 1 may include an actuator 18 to toggle thefirst engagement element 16 between an engaged state and an unengagedstate. The actuator 18 may be a lever, a handle, knob, button or anyother suitable actuator.

FIG. 19 shows a further embodiment wherein the actuator 18 is a lever.The lever 18 is pulled downwards, as shown by arrow D to release thebracket 3 from formwork 15. FIGS. 15-18 show other embodiments includingan actuator 18 to toggle between an engaged and unengaged state ofconnection. The actuator 18 may also be readily removable from thebracket. This may be useful, for example, to prevent tampering with thebracket when it is left unattended.

The second engagement element may act as a spacer when formwork isarranged in stacks (e.g. for transportation or storage). This increasesairflow between the formwork members allowing faster drying after useand reduced distortion/warping of the formwork. FIG. 20 shows stackedformwork 15 including second engagement elements 17 creating spacesbetween formworks 15.

The invention facilitates removal of bracing from formwork in anon-disruptive manner which does not affect the concrete. The result isthat bracing can be removed from formwork much sooner than undertraditional bracing methods. This saves construction time and cost. Insome applications it is expected that the bracing could be removed fromthe formwork the same day as concrete is poured.

The concrete formwork brace of the present invention, when equipped witha suitable connector, does not damage formwork each time it is attachedto and detached from formwork. It is highly reusable, and saves onmaterials and cost.

The brace of the present invention can be readily adjusted both manuallyand using automated power tools. The adjustment is quick and simple, andcan be made before or after the brace has been secured to the formwork.

There is thus provided a concrete formwork brace which is sturdy andreadily adjustable to accommodate different required heights and/ororientations. The quadrilateral geometry of the brace provides rigidityensuring that formwork is kept in place. The brace is quick, easy andconvenient to set up. Angular and height adjustments can be made withease.

The four pivot points of adjustment allow angular and height adjustmentsof the bracket to be made with extreme precision. This arrangement alsoallows the brace to be used on sloping surfaces.

There is provided a brace which can be quickly secured to and detachedfrom formwork, using a quick release mechanism. This improves theefficiency of completing the concrete forming as users can quickly setup the braces and move them from formwork to formwork.

While the present invention has been illustrated by the description ofthe embodiments thereof, and while the embodiments have been describedin detail, it is not the intention of the Applicant to restrict or inany way limit the scope of the appended claims to such detail. Further,the above embodiments may be implemented individually, or may becombined where compatible. Additional advantages and modifications,including combinations of the above embodiments, will readily appear tothose skilled in the art. Therefore, the invention in its broaderaspects is not limited to the specific details, representative apparatusand methods, and illustrative examples shown and described. Accordingly,departures may be made from such details without departure from thespirit or scope of the Applicant's general inventive concept.

1. A concrete formwork brace including: a base, a bracket configured tosupport a concrete formwork, a first length adjustable arm, connected tothe base and the bracket, and a second arm connected to the base and thebracket; wherein the connection between the first arm and the base isvertically offset from the connection between the second arm and thebase, wherein the connection between the first arm and the bracket isvertically offset from the connection between the second arm and thebracket; and wherein the first arm is length adjustable such as toadjust the orientation of the bracket.
 2. The concrete formwork brace ofclaim 1, wherein the second arm is length adjustable.
 3. The concreteformwork brace of claim 1 wherein the connection between the first armand the base is horizontally offset from the connection between thesecond arm and the base.
 4. The concrete formwork brace of claim 1wherein the connection between the first arm and the base is at a firstend of the base and the connection between the second arm and the baseis at an intermediate position between the first end of the base and asecond end of the base.
 5. The concrete formwork brace of claim 4wherein the connection between the second arm and the base is centrallylocated on the base.
 6. The concrete formwork brace of claim 1 whereinthe connection between the second arm and the base is verticallyelevated relative to the connection between the first arm and the base.7. The concrete formwork brace of claim 1 wherein the base has mountingfeatures for securing the base to a ground surface.
 8. The concreteformwork brace of claim 7 wherein the mounting features are aperturesconfigured to receive fasteners for securing the base to a groundsurface.
 9. The concrete formwork brace of claim 1 wherein the brackethas mounting features for securing the bracket to formwork.
 10. Theconcrete formwork brace of claim 9 wherein the bracket has aperturesconfigured to receive fasteners securing the bracket to formwork
 11. Theconcrete formwork brace of claim 1 wherein the bracket is configured torest, in use, on a ground surface.
 12. The concrete formwork brace ofclaim 1 wherein the bracket is height-adjustable.
 13. The concreteformwork brace of claim 1 wherein the brace includes a level indicator.14. The concrete formwork brace of claim 1, wherein the first lengthadjustable arm is length-adjustable by rotation of a threaded element.15. The concrete formwork brace of claim 2, wherein the second arm islength-adjustable by rotation of a threaded element.
 16. The concreteformwork brace of claim 1 wherein the connection between the first armand the bracket is a pivotal connection and the connection between thesecond arm and the bracket is a pivotal connection.
 17. The concreteformwork brace of claim 1 wherein the connection between the first armand the base is a pivotal connection and the connection between thesecond arm and the base is a pivotal connection.
 18. A concrete formworkbrace as claimed in claim 1 wherein the bracket includes a firstengagement element configured to engage with a cooperating secondengagement element on a concrete formwork to define a releasableconnection between the bracket and the formwork.
 19. The concreteformwork brace of claim 18 wherein the releasable connection is a clampconnection.
 20. The concrete formwork brace of claim 18 wherein thereleasable connection is a hook connection.